Principles of genetics applied to medicine

Abstract

Mendelian genetics, ie, the rules governing the inheritance of single major genes, is not only a matter of breeding experiments, observation of traits in large families, or consanguinity in parents but also, to some extent, a matter of logic which permits the understanding of the mendelian rules from a few data of classic biology. Rules of autosomal and X-linked inheritance and their pertinent language are reviewed operationally, and expressivity, penetrance, heterogeneity, and pleiotropy are explained.